Marital status is a recognized social determinant of health, but its association with outcomes in cardiopulmonary exercise testing (CPX) cohorts remains unclear. A retrospective, single-center observational study published in Environmental Health and Preventive Medicine evaluated the association between marital status and mortality in patients with cardiac disease (CD) undergoing CPX.

Consecutive patients who underwent post-discharge CPX between 2008 and 2020 were included. A total of 4,681 participants (mean age 69 years; 73% male) were categorized as married or unmarried, with the latter including individuals who were never married, divorced, or widowed.

The primary outcome was all-cause mortality, and the secondary outcome was cardiovascular (CV) mortality. Cox proportional hazards models estimated adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs). Model 1 adjusted for age and sex, while Model 2 additionally adjusted for peak oxygen uptake (VO₂) to account for exercise capacity.

Among the cohort, 1,117 were unmarried and 3,564 were married. Married status was associated with a lower risk of all-cause mortality in Model 1 (aHR 0.75; 95% CI 0.62-0.91; P<0.001), which remained significant after adjustment for peak VO₂ in Model 2 (aHR 0.79; 95% CI 0.65-0.96; P=0.002). For CV mortality, estimates were consistent in direction (Model 1: aHR 0.64; 95% CI 0.44-0.93; P=0.019; Model 2: aHR 0.69; 95% CI 0.47-1.02; P=0.061).

These findings indicate that married status was associated with lower all-cause mortality in patients with cardiac disease undergoing CPX. The association was attenuated but persisted after adjustment for peak VO₂, suggesting that differences in exercise capacity may contribute but do not fully account for the observed association.